Allelic loss of chromosomes 16q and 10q in human prostate cancer.

Recent advances in understanding the molecular genetics of common adult tumors have indicated that multiple genetic alterations including the activation of oncogenes and the inactivation of tumor suppressor genes are important in the pathogenesis of these tumors. Loss of heterozygosity is a hallmark of tumor suppressor gene inactivation and has been used to identify chromosomal regions that contain these genes. We have examined allelic loss in the most common tumor in men, prostate cancer.

Differential effects of growth factor antagonists on neoplastic and normal prostatic cells.

Growth factors such as epidermal growth factor and fibroblast growth factor have been suggested to be involved as paracrine or autocrine mediators of androgen action in normal and malignant prostatic cells. Suramin and protamine are potent in vitro growth factor antagonists. To evaluate the effect of growth factor antagonists on prostatic growth, suramin and protamine were administered to castrated rats simultaneously receiving exogenous testosterone replacement in an attempt to block androgen-dependent restoration of the normal rat ventral prostate.

Biosynthesis of titin in cultured skeletal muscle cells.

Although significant progress has been made regarding the structure and function of titin, little data exist on the biosynthesis of this large protein in developing muscle. Using pulse-labeling with [35S]methionine and immunoprecipitation with an anti-titin mAb, we have examined the biosynthesis of titin in synchronized cultures of skeletal muscle cells derived from day 12 chicken embryos. We find that: (a) titin synthesis increases greater than 4-fold during the first week in culture and during this same time period, synthesis of muscle-specific myosin heavy chain increases greater than 12-fold; (b) newly synthesized titin has a t1/2 of approximately 70 h; (c) titin is resistant to extraction with Triton X-100 both during and immediately after its synthesis.

Assembly of vimentin in cultured cells varies with cell type.

To examine how vimentin assembles into the cytoskeletons of cultured cells, we used pulse labeling with [35S]methionine, cell fractionation with Triton X-100, and immunoprecipitation with a monoclonal antibody that binds both nascent and full-length vimentin polypeptides. In embryonic muscle cells, fibroblasts, and erythroid cells, we find two populations of newly synthesized vimentin. One population is found on the cytoskeleton immediately after a 2-min pulse with labeled methionine; the other is delayed in its association with the cytoskeleton and has a measurable rate of disappearance from the extractable pool.

Cotranslational assembly of myosin heavy chain in developing cultured skeletal muscle.

To examine how nascent myosin heavy chains associate with the cytoskeletons of developing muscle cells, we used pulse labeling, cell fractionation, and immunoprecipitation. More than 80% of nascent myosin heavy chains associate with the cytoskeleton. More than one-third of these nascent chains are not released by puromycin and/or RNase.

Time lapse videomicroscopic identification of Dunning R-3327 adenocarcinoma and normal rat prostate cells.

A method for accurate prediction of prognosis in human prostatic cancer does not exist. The limitations of pathologic grading systems may result from the failure of standard pathological examination of fixed dead tissue to accurately assess the biological behavior of live tumor cells. Many of the sublines of the Dunning R-3327 rat adenocarcinoma are histologically similar yet differ widely in their metastatic potential.

Adenocarcinoma of the canine prostate: immunohistochemical examination for secretory antigens.

Thirty-one canine adenocarcinomas of prostatic origin were examined immunohistochemically with antibodies generated against three prostate-specific antigens by using a peroxidase-antiperoxidase technique. Primary antibodies included two generated with human prostatic antigens (PSA, PSAP) and one generated with a canine prostatic antigen (CPSP). Eight of 31 adenocarcinomas were positive with CPSP, two were positive with PSA, and three were PSAP positive.

Establishment and characterization of seven Dunning rat prostatic cancer cell lines and their use in developing methods for predicting metastatic abilities of prostatic cancers.

In vitro cell lines were established from seven biologically distinct in vivo Dunning R3327 rat prostatic tumor sublines. Some of these in vitro cell lines (i.e.

Immunological localization and quantitation of the androgen-dependent secretory protease of the canine prostate.

We have recently reported on the isolation and characterization of the predominant protein of canine prostatic fluid and the subsequent identification of this protein as a proteolytic enzyme. In this report, we described the preparation and characterization of a rabbit antiserum against this secretory protease which was purified from canine prostatic fluid by preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Specificity of the antiserum has been established by immunoblot analysis and immunoprecipitation of the secretory protease present in canine prostatic fluid and tissue homogenates.

Immunogold probes for electron microscopy: evaluation of staining by fluorescence microscopy.

A method is presented whereby the staining of intracellular structures with immunogold probes for electron microscopy can be evaluated at the light microscopic level. Methanol-fixed monolayers of cultured Dunning R-3327-H rat prostatic adenocarcinoma cells were stained for cytokeratins using a two-step immunogold technique consisting of primary anti-keratin antibody followed by gold-labeled secondary antibody. Bound immunogold probe was then visualized with a fluorescent tertiary anti-immunogold probe antibody.

The predominant protein of canine seminal plasma is an enzyme.

One protein in canine seminal plasma accounts for over 90% of the total protein and is present at the high concentration of approximately 10 mg/ml. We demonstrate that this predominant protein is a proteolytic enzyme. The enzyme has been purified and migrates as a single symmetrical peak of apparent molecular mass of 29,000 daltons on a column of Sephadex G-75 and as a single band of approximately 30,000 daltons when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under nonreducing conditions.

Isolation and characterization of the major androgen-dependent glycoprotein of canine prostatic fluid.

Canine prostatic fluid, analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under non-reducing conditions, is characterized by the presence of a single diffuse band (Mr approximately 30,000) which accounts for over 90% of the total protein. The biosynthesis of this protein is under androgen control. Castration results in the disappearance of this protein, whereas its presence in the prostate can be maintained in the castrated animal with exogenous androgen.

Differential effects of estrogen treatment on canine seminal plasma components.

In castrate dogs, complete androgen-dependent restoration of seminal plasma content of fluid, electrolytes, and protein was induced by testosterone treatment alone. In contrast, a combination of androgen and estrogen treatment selectively reduced only the androgen induced stimulation of the electrolyte and fluid components without altering the total amount of protein secreted. Spontaneous cystic prostatic hyperplasia was found to be characterized by a similar decrease in total fluid and electrolyte content without a concomitant decrease in the total amount of protein in the seminal plasma.

Models for development of nonreceptor methods for distinguishing androgen-sensitive and -insensitive prostatic tumors.

From the original Dunning R-3327 rat prostatic adenocarcinoma, several distinct sublines have been obtained. These sublines include a well-differentiated, slow-growing, androgen-sensitive tumor (R-3327-H); a well-differentiated, slow-growing, androgen-insensitive tumor (R-3327-HI); and a fast-growing, androgen-insensitive, anaplastic tumor (R-3327-AT). These three sublines were compared in order to develop new model methods for the prediction of the androgen sensitivity and the degree of differentiation of prostatic adenocarcinomas.

Biochemical diagnosis in sickle cell disease.

Seventy-four sicklers with bone pain had blood taken for biochemical analysis of the haemoglobins carried. Sixty-five patients with sickle cell disease diagnosed as Hb S/S disease, five patients diagnosed as Hb A/S and four patients with three haemoglobin bands corresponding to Hb's A, S and C were used in this quantitative reassessment on cellulose acetate. Haemoglobin A2 level was determined in all cases and alkali resistant haemoglobin level in twenty-nine cases.